The East Africa - Arabia topographic swell is an anomalously high-elevation region of ∼4000 km long (from southern Ethiopia to Jordan) and ∼ 1500 km wide (from Egypt to Saudi Arabia) extent. The swell is dissected by the Main Ethiopian, Red Sea, and Gulf of Aden rifts, and characterized by widespread basaltic volcanic deposits emplaced from the Eocene to the present. Geochemical and geophysical data confirm the involvement of mantle processes in swell formation; however, they have not been able to fully resolve some issues, e.g., regarding the number and location of plumes and uplift patterns. This study addresses these questions and provides a general evolutionary model of the region by focusing on the present topographic configuration through a quantitative analysis and correlating long and intermediate wavelength features with mantle and rifting processes. Moreover, the isostatic and dynamic components of topography have been evaluated considering a range of seismic tomographic models for the latter. When interpreted jointly with geological data including volcanic deposits, the constraints do imply causation by a single process which shaped the past and present topography of the study area: the upwelling of the Afar superplume. Once hot mantle material reached the base of the lithosphere below the Horn of Africa during the Late Eocene, the plume flowed laterally toward the Levant area guided by pre-existing discontinuities in the Early Miocene. Plume material reached the Anatolian Plateau in the Late Miocene after slab break-off and the consequent formation of a slab window. During plume material advance, buoyancy forces led to the formation of the topographic swell and tilting of the Arabia Peninsula. The persistence of mantle support beneath the study area for tens of million years also affected the formation and evolution of the Nile and Euphrates-Tigris fluvial networks. Subsequently, surface processes, tectonics, and volcanism partly modified the initial topography and shaped the present-day landscape.

中文翻译：

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东非的隆起——阿拉伯崛起


东非-阿拉伯地形隆起是一个异常高海拔地区，长约 4000 公里（从埃塞俄比亚南部到约旦），宽约 1500 公里（从埃及到沙特阿拉伯）。该涌浪被埃塞俄比亚、红海和亚丁湾主要裂谷所分割，其特征是从始新世至今广泛分布的玄武岩火山沉积物。地球化学和地球物理数据证实了地幔过程参与了膨胀的形成；然而，他们未能完全解决一些问题，例如有关羽流和隆起模式的数量和位置的问题。这项研究解决了这些问题，并通过定量分析关注当前的地形结构，并将长波和中波特征与地幔和裂谷过程联系起来，提供了该地区的一般演化模型。此外，考虑了后者的一系列地震层析成像模型，评估了地形的等静压和动态分量。当与包括火山沉积物在内的地质数据一起解释时，这些约束确实意味着塑造研究区域过去和现在地形的单一过程的因果关系：阿法尔超羽流的上升。一旦热地幔物质在晚始新世到达非洲之角下方的岩石圈底部，羽流就会在早中新世预先存在的不连续性的引导下横向流向黎凡特地区。在板片断裂并随后形成板片窗之后，羽流物质在中新世晚期到达安纳托利亚高原。在羽流物质前进过程中，浮力导致阿拉伯半岛地形隆起和倾斜的形成。 研究区域下方地幔支撑持续数千万年也影响了尼罗河和幼发拉底河-底格里斯河网络的形成和演化。随后，地表过程、构造和火山活动部分改变了最初的地形并塑造了当今的景观。